CN202917957U - Relay switching-off and switching-on control circuit for ammeter and intelligent ammeter - Google Patents
Relay switching-off and switching-on control circuit for ammeter and intelligent ammeter Download PDFInfo
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- CN202917957U CN202917957U CN 201220557811 CN201220557811U CN202917957U CN 202917957 U CN202917957 U CN 202917957U CN 201220557811 CN201220557811 CN 201220557811 CN 201220557811 U CN201220557811 U CN 201220557811U CN 202917957 U CN202917957 U CN 202917957U
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Abstract
Disclosed in the utility model is a relay switching-off and switching-on control circuit for an ammeter. The control circuit comprises a capacitance-resistance voltage reduction circuit, a power control circuit, a constant-current charging circuit, an equalizing circuit and a switching circuit. Voltage signals of zero line N and a live wire L of a power grid are accessed to an input terminal of the capacitance-resistance voltage reduction circuit; and an output terminal of the capacitance-resistance voltage reduction circuit is electrically connected to the power control circuit. The power control circuit is electrically connected to the constant-current charging circuit which is electrically connected to the equalizing circuit and the switching circuit, wherein the equalizing circuit and the switching circuit are coupled with each other. And the switching circuit carries out switching-off and switching-on motions by a relay. In addition, an intelligent ammeter is also disclosed by the utility model. The intelligent ammeter consists of a processor, a display circuit, a power supply VCC, and the relay switching-off and switching-on control circuit. According to the utility model, the circuit enables the hidden fault trouble caused by overvoltage or undervoltage of the switching-off and switching-on motions to be effectively avoided; and the circuit has a simple structure. Meanwhile, a power supply scheme with effective utilization of a power supply is also provided.
Description
Technical field
The utility model relates generally to a kind of switching on/control circuit that is applied to ammeter, and a kind of intelligent electric meter with this control circuit.
Background technology
Along with the development need of intelligent grid, the functions such as pre-payment, carrier communication, remote meter reading, Long-distance Control are applied on the ammeter gradually.The switching on/function of ammeter becomes the indispensable circuit of control power supply.Traditional switching on/circuit is by transformer-supplied, and the H bridge is controlled switching on/, and exist following problem: switching on/voltage causes the switching on/baulk not when low-voltage is inputted; The H bridge circuit is complicated, and the inverse electromotive force that protection Design is improper when easily being turned off punctures triode; The transformer frequency response internal resistance is little, and upper and lower bridge arm together conducting meeting burning triode causes the problems such as switching on/circuit malfunction.
The utility model content
The utility model is intended to solve the defective that prior art exists, design a kind of switching on/control circuit that is applied to ammeter, can effectively avoid electric current in the switching on/circuit excessive and cause losing efficacy or situation about damaging occurs, and a kind of ammeter with energy-saving and cost-reducing power source design is provided.
In order to realize above-mentioned purpose of design, the utility model is achieved through the following technical solutions:
Technical scheme 1: a kind of ammeter relay switching on/control circuit, comprise capacitance-resistance voltage reduction circuit, power control circuit, further comprise constant-current charging circuit, equalizer circuit and switching circuit, wherein electrical network zero line N and live wire L voltage signal access the input of capacitance-resistance voltage reduction circuit, the output of described capacitance-resistance voltage reduction circuit is electrically connected to power control circuit, described power control circuit is electrically connected to constant-current charging circuit, described constant-current charging circuit further is electrically connected to equalizer circuit and the switching circuit that intercouples, and described switching circuit carries out the switching on/action by its relay.
Further, in preferred embodiment of the present utility model, described capacitance-resistance voltage reduction circuit is by resistance MOV1, R1, safety capacitor C 1, diode D1, D3, D4 and electrochemical capacitor E1 form, wherein between the zero line N and live wire L circuit of capacitance-resistance voltage reduction circuit, be equipped with resistance MOV1, described resistance MOV1 is piezo-resistance; Further be equipped with diode D3, D4, described diode D3, D4 are voltage stabilizing didoe, are used for the external power supply of capacitance-resistance voltage reduction circuit is set clamp voltage; Further be equipped with electrochemical capacitor E1.
Further, in preferred embodiment of the present utility model, described power control circuit is by resistance R 2, R3, R4, R5, triode Q1, Q5, diode D2 forms, and wherein resistance R 2 is current sampling resistor, and it is connected to voltage stabilizing didoe D4, outside an external power supply was powered to ammeter by capacitance-resistance voltage reduction circuit, residual current flow back into capacitance-resistance voltage reduction circuit by described resistance R 2; Resistance R 3 is connected in triode Q5 by voltage stabilizing didoe D3 between the D4, triode Q1 connects between the Q5 and establishes resistance R 4, R5.
Further, in preferred embodiment of the present utility model, described equalizer circuit is by voltage stabilizing didoe D5, D6, resistance R 8, and R9 and switching on/electric capacity E2, E3 forms, wherein said switching on/electric capacity E2, E3 is external to an external power supply; Described diode D5, D6 are connected to switching on/electric capacity E2, and E3 is so that switching on/electric capacity E2, the impartial and mA level current loss of the charging voltage of E3; Described resistance R 8, R9 further is connected to switching on/electric capacity E2, E3 and be external to the ADC sample port of ammeter processor.
Further, in preferred embodiment of the present utility model, described constant-current charging circuit is by resistance R 7, R6 and triode Q2, Q3 forms, and wherein resistance R 7 is connected between the emitter and base stage of triode Q2, and resistance R 6 is connected between the base stage and collector electrode of triode Q3, described triode Q2, Q3 intercouple to form a crossing current circuit.
Further, in preferred embodiment of the present utility model, described switching circuit is by resistance R 10, R11, and R12, R13, R14, R15, triode Q4, Q6, Q7 and relay form, and wherein resistance R 13, and R14 forms pull down resistor; Triode Q4, Q6 and resistance R 10, R11, R12 are of coupled connections closed with control relay; Triode Q7 and resistance R 15 are of coupled connections and disconnect with control relay.
Further, in preferred embodiment of the present utility model, when the voltage at resistance R 2 two ends reaches the conducting voltage of triode Q5, the voltage at resistance R 2 two ends makes described triode Q5 conducting by resistance R 3, from and by resistance R 5 so that triode Q1 conducting, described triode Q1 powers to late-class circuit.When the late-class circuit supply current increased, the electric current that flows through resistance R 2 reduced finally so that triode Q5 is in magnifying state, and triode Q1 is pulled to magnifying state with the supply current of restriction to late-class circuit by resistance R 4.When the required operating current of ammeter increases, after resistance R 2 is regulated the electric current of late-class circuit is reduced.When meter circuit needs the Transient Currents power supply, be stored in described switching on/electric capacity E2, the electric energy among the E3 provides the spark electric current by diode D2; Power control circuit preferentially guarantees normality power supply and the Transient Currents power demands of ammeter functional circuit part, and unnecessary electric energy is powered to the abnormal operating circuit of rear end again.As switching on/electric capacity E2, during E3 underfill electricity, 6 couples of triode Q3 of resistance R are drop-down to make its conducting, electric current by resistance R 7 and triode Q3 to rear end switching on/electric capacity E2, the E3 charging, the voltage drop that current flowing resistance R7 produces is so that triode Q2 conducting, and triode Q2 conducting has limited again the conducting of triode Q3, thereby the electric current of limiting resistance R7 forms a crossing current circuit simultaneously.As described switching on/electric capacity E2, when E3 was full of electricity, described crossing current circuit itself is current sinking no longer, has improved power-efficient.It is constant that constant-current charging circuit is compared the whole charging ring current of crosstalk resistance current-limiting charge, and the impulse current when having reduced to power on has shortened the charging interval.
Technical scheme 2: a kind of intelligent electric meter, it comprises processor and display circuit, further comprise power supply VCC, and foregoing relay switching on/control circuit, wherein capacitance-resistance voltage reduction circuit connects power supply VCC and passes through its diode D3, and D4 is 24V with the magnitude of voltage clamper of power supply VCC; Described power supply VCC further is connected to display circuit, processor and equalizer circuit and operating voltage is provided for it; Described processor is connected to equalizer circuit (4) by the ADC sample port and judges its switching on/electric capacity E2, and whether E3 charges complete to carry out the switching on/operation.
Further, in preferred embodiment of the present utility model, processor can be judged switching on/electric capacity E2 by the ADC sample port, and whether E3 charges and completely can carry out the switching on/operation, has improved the reliability of each switching on/operation.
Further, in preferred embodiment of the present utility model, resistance R 13, the pull down resistor that R14 forms guarantees that processor can not carry out misoperation to relay before finishing the I/O initialization.When closing operation, the switching signal of processor is by R12, and Q6, R11 are so that the Q4 conducting, and power supply makes the relay adhesive to the electric energy of storing among the E2 to relay by Q4; When operating a switch operation, the signal of operating a switch of processor makes the Q7 conducting by R15, and power supply is operated a switch relay to the electric energy of storing among the E3 to relay by Q7.
The beneficial effects of the utility model are apparent, and the utility model switching on/circuit can effectively be avoided because of switching on/electric voltage over press or the not enough potential faults that causes, and circuit structure is simple, and a kind of power source design that effectively utilizes supply power voltage is provided simultaneously.The technical solution of the utility model scope of application is extremely extensive, and can reduce cost to the ammeter internal circuit design.
Description of drawings
Preferred implementation of the present utility model will be following by embodying with reference to the mode of accompanying drawing in detail, and the identical function components/modules among the figure is with same-sign mark in addition, wherein
Fig. 1 is the circuit theory diagrams of the preferred embodiment of the utility model ammeter relay switching on/control circuit;
Fig. 2 is the structure principle chart of the utility model intelligent electric meter.
Embodiment
With reference to Fig. 1, the preferred embodiment of the utility model ammeter relay switching on/control circuit comprises capacitance-resistance voltage reduction circuit 1, power control circuit 2, further comprise constant-current charging circuit 3, equalizer circuit 4 and switching circuit 5, wherein electrical network zero line N and live wire L voltage signal access the input of capacitance-resistance voltage reduction circuit 1, the output of described capacitance-resistance voltage reduction circuit 1 is electrically connected to power control circuit 2, described power control circuit 2 is electrically connected to constant-current charging circuit 3, described constant-current charging circuit 3 further is electrically connected to equalizer circuit 4 and the switching circuit 5 that intercouples, and described switching circuit 5 carries out the switching on/action by its relay K.
In preferred embodiment of the present utility model, capacitance-resistance voltage reduction circuit 1 is by resistance MOV1, R1, safety capacitor C 1, diode D1, D3, D4 and electrochemical capacitor E1 form, wherein be equipped with resistance MOV1 between the zero line N of capacitance-resistance voltage reduction circuit 1 and live wire L circuit, described resistance MOV1 is piezo-resistance; Further be equipped with diode D3, D4, described diode D3, D4 are voltage stabilizing didoe, are used for the external power supply VCC of capacitance-resistance voltage reduction circuit (1) is set clamp voltage; Further be equipped with electrochemical capacitor E1.Clamper by D3 and D4 is so that VCC voltage is 24V.The VCC circuit is except being the computation chip of ammeter, MCU, the outer switching on/capacitor charging that is also responsible for of the power supplies such as liquid crystal drive.
In preferred embodiment of the present utility model, power control circuit 2 is by resistance R 2, R3, R4, R5, triode Q1, Q5, diode D2 forms, wherein resistance R 2 is current sampling resistor, it is connected to voltage stabilizing didoe D4, and outside an external power supply VCC powered by 1 pair of ammeter of capacitance-resistance voltage reduction circuit, residual current flow back into capacitance-resistance voltage reduction circuit 1 by described resistance R 2; Resistance R 3 is connected in triode Q5 by voltage stabilizing didoe D3 between the D4, triode Q1 connects between the Q5 and establishes resistance R 4, R5.
Wherein, R2 is current sampling resistor, and the constant-current source that is comprised of capacitance-resistance voltage reduction circuit 1 is except giving the ammeter functional circuit for the electric current, and remaining electric current flows back to constant-current source circuit by R2.When the voltage at R2 two ends reaches the conducting voltage of Q5, the voltage at R2 two ends makes the Q5 conducting by R3, the Q5 conducting is passed through again R5 so that the Q1 conducting, Q1 powers to back-end circuit, when the back-end circuit supply current increases, the electric current that flows through R2 reduces final Q5 and is in magnifying state, and Q1 is in magnifying state and has limited supply current to back-end circuit by drawing on the R4.When the increase in demand of ammeter functional circuit part electric current, regulate rear electric current to back-end circuit by R2 and reduce.When functional circuit needed the Transient Currents power supply, the electric energy that is stored in the switching on/electric capacity can provide the spark electric current by D2 again.Power control circuit preferentially guarantees normality power supply and the Transient Currents power demands of ammeter functional circuit part, and unnecessary electric energy is powered to the abnormal operating circuit of rear end again.
With reference to Fig. 2, in preferred embodiment of the present utility model, equalizer circuit 4 is by voltage stabilizing didoe D5, D6, resistance R 8, and R9 and switching on/electric capacity E2, E3 forms, and wherein said switching on/electric capacity E2, E3 are external to an external power supply VCC; Described diode D5, D6 are connected to switching on/electric capacity E2, and E3 is so that its charging voltage is impartial and be mA level current loss; Described resistance R 8, R9 further is connected to switching on/electric capacity E2, E3 and be external to the ADC sample port of ammeter processor 10.D5, D6 have guaranteed that the switching on/capacitor charging voltage of 2 series connection equates, avoids again the mA level current loss of conventional capacitance partial pressure resistive band simultaneously.The divider resistance that R8 and R9 form connects the ADC thief hatch of processor, and processor can judge whether switching on/electric capacity charges by the ADC sampling completely can carry out the switching on/operation, has improved the reliability that each switching on/operates.
See figures.1.and.2, in preferred embodiment of the present utility model, constant-current charging circuit 3 is by resistance R 7, R6 and triode Q2, Q3 forms, and wherein resistance R 7 is connected between the emitter and base stage of triode Q2, and resistance R 6 is connected between the base stage and collector electrode of triode Q3, described triode Q2, Q3 intercouple to form a crossing current circuit.As switching on/electric capacity E2, during E3 underfill electricity, R6 causes the Q3 conducting to Q3 is drop-down, and electric current is by R7, and Q3 is to rear end switching on/capacitor charging, electric current flows through the voltage drop of R7 generation so that the Q2 conducting, the Q2 conducting has limited again the conducting of Q3, thereby the electric current that has limited again conversely R7 forms a crossing current circuit, when rear end switching on/electric capacity is full of electricity, crossing current circuit itself is current sinking no longer, has improved power-efficient.It is constant that constant-current charging circuit is compared the whole charging ring current of crosstalk resistance current-limiting charge, and the impulse current when having reduced to power on has shortened the charging interval.
In preferred embodiment of the present utility model, switching circuit 5 is by several resistance R 10, R11, and R12, R13, R14, R15, triode Q4, Q6, Q7 and relay K form, and wherein resistance R 13, and R14 forms pull down resistor; Triode Q4, Q6 and resistance R 10, R11, R12 are of coupled connections closed with control relay K; Triode Q7 and resistance R 15 are of coupled connections and disconnect with control relay K.R13, the pull down resistor that R14 forms guarantee that processor can not carry out misoperation to relay before finishing the I/O initialization.During closing operation, the switching signal of processor is by R12, and Q6, R11 are so that the Q4 conducting, and power supply makes the relay adhesive to the electric energy of storing among the E2 to relay by Q4.When operating a switch operation, the signal of operating a switch of processor makes the Q7 conducting by R15, and power supply is operated a switch relay to the electric energy of storing among the E3 to relay by Q7.
When the voltage at resistance R 2 two ends reached the conducting voltage of triode Q5, the voltage at resistance R 2 two ends made described triode Q5 conducting by resistance R 3, from and by resistance R 5 so that triode Q1 conducting, described triode Q1 powers to late-class circuit; When the late-class circuit supply current increased, the electric current that flows through resistance R 2 reduced until triode Q5 is in magnifying state, and triode Q1 is pulled to magnifying state with the supply current of restriction to late-class circuit by resistance R 4; When the required operating current of ammeter increases, after resistance R 2 is regulated the electric current of late-class circuit is reduced; When meter circuit needs the Transient Currents power supply, be stored in described switching on/electric capacity E2, the electric energy among the E3 provides the spark electric current by diode D2; As switching on/electric capacity E2, during E3 underfill electricity, 6 couples of triode Q3 of resistance R are drop-down to make its conducting, electric current by resistance R 7 and triode Q3 to rear end switching on/electric capacity E2, the E3 charging, the voltage drop that current flowing resistance R7 produces is so that triode Q2 conducting, and triode Q2 conducting has limited again the conducting of triode Q3, thereby the electric current of limiting resistance R7 forms a crossing current circuit simultaneously.
Fig. 2 shows a kind of intelligent electric meter, it comprises processor 10 and display circuit 20, it is characterized in that: further comprise power supply VCC, and relay switching on/control circuit 30 as claimed in claim 1, wherein capacitance-resistance voltage reduction circuit 1 connects power supply VCC and passes through its diode D3, and D4 is 24V with the magnitude of voltage clamper of power supply VCC; Described power supply VCC further is connected to display circuit 20, processor 10 and equalizer circuit 4 and operating voltage is provided for it; Described processor 10 is connected to equalizer circuit 4 by the ADC sample port and judges its switching on/electric capacity E2, and whether E3 charges complete to carry out the switching on/operation.
Being preferred implementation of the present utility model only below, being intended to embody outstanding technique effect of the present utility model and advantage, is not to be restriction to the technical solution of the utility model.Those skilled in the art will appreciate that all modifications of having done based on the utility model technology contents, variation or substitute technology feature, all should be covered by in the technology category of the utility model claims opinion.
Claims (8)
1. ammeter relay switching on/control circuit, comprise capacitance-resistance voltage reduction circuit (1), power control circuit (2), it is characterized in that: further comprise constant-current charging circuit (3), equalizer circuit (4) and switching circuit (5), wherein electrical network zero line N and live wire L voltage signal access the input of capacitance-resistance voltage reduction circuit (1), the output of described capacitance-resistance voltage reduction circuit (1) is electrically connected to power control circuit (2), described power control circuit (2) is electrically connected to constant-current charging circuit (3), described constant-current charging circuit (3) further is electrically connected to equalizer circuit (4) and the switching circuit (5) that intercouples, and described switching circuit (5) carries out the switching on/action by its relay (K).
2. ammeter relay switching on/control circuit as claimed in claim 1, it is characterized in that: described capacitance-resistance voltage reduction circuit (1) is by resistance MOV1, R1, safety capacitor C 1, diode D1, D3, D4 and electrochemical capacitor E1 form, wherein between the zero line N and live wire L circuit of capacitance-resistance voltage reduction circuit (1), be equipped with resistance MOV1, described resistance MOV1 is piezo-resistance; Further be equipped with diode D3, D4, described diode D3, D4 are voltage stabilizing didoe, are used for the external power supply VCC of capacitance-resistance voltage reduction circuit (1) is set clamp voltage; Further be equipped with electrochemical capacitor E1.
3. ammeter relay switching on/control circuit as claimed in claim 1 or 2, it is characterized in that: described power control circuit (2) is by resistance R 2, R3, R4, R5, triode Q1, Q5, diode D2 forms, wherein resistance R 2 is current sampling resistor, it is connected to voltage stabilizing didoe D4, and outside an external power supply VCC powered to ammeter by capacitance-resistance voltage reduction circuit (1), residual current flow back into capacitance-resistance voltage reduction circuit (1) by described resistance R 2; Resistance R 3 is connected in triode Q5 by voltage stabilizing didoe D3 between the D4, triode Q1 connects between the Q5 and establishes resistance R 4, R5.
4. ammeter relay switching on/control circuit as claimed in claim 1, it is characterized in that: described equalizer circuit (4) is by voltage stabilizing didoe D5, D6, resistance R 8, R9 and switching on/electric capacity E2, E3 forms, and wherein said switching on/electric capacity E2, E3 are external to an external power supply VCC; Described diode D5, D6 are connected to switching on/electric capacity E2, and E3 is so that its charging voltage is impartial and be mA level current loss; Described resistance R 8, R9 further is connected to switching on/electric capacity E2, E3 and be external to the ADC sample port of ammeter processor (10).
5. ammeter relay switching on/control circuit as claimed in claim 1, it is characterized in that: described constant-current charging circuit (3) is by resistance R 7, R6 and triode Q2, Q3 forms, wherein resistance R 7 is connected between the emitter and base stage of triode Q2, resistance R 6 is connected between the base stage and collector electrode of triode Q3, and described triode Q2, Q3 intercouple to form a crossing current circuit.
6. ammeter relay switching on/control circuit as claimed in claim 1, it is characterized in that: described switching circuit (5) is by several resistance R 10, R11, R12, R13, R14, R15, triode Q4, Q6, Q7 and relay (K) form, and wherein resistance R 13, and R14 forms pull down resistor; Triode Q4, Q6 and resistance R 10, R11, R12 are of coupled connections with control relay (K) closure; Triode Q7 and resistance R 15 are of coupled connections and disconnect with control relay (K).
7. such as each described ammeter relay switching on/control circuit in the claim 1 to 6, it is characterized in that: when the voltage at resistance R 2 two ends reaches the conducting voltage of triode Q5, the voltage at resistance R 2 two ends makes described triode Q5 conducting by resistance R 3, from and by resistance R 5 so that triode Q1 conducting, described triode Q1 powers to late-class circuit; When the late-class circuit supply current increased, the electric current that flows through resistance R 2 reduced until triode Q5 is in magnifying state, and triode Q1 is pulled to magnifying state with the supply current of restriction to late-class circuit by resistance R 4; When the required operating current of ammeter increases, after resistance R 2 is regulated the electric current of late-class circuit is reduced; When meter circuit needs the Transient Currents power supply, be stored in described switching on/electric capacity E2, the electric energy among the E3 provides the spark electric current by diode D2; As switching on/electric capacity E2, during E3 underfill electricity, 6 couples of triode Q3 of resistance R are drop-down to make its conducting, electric current by resistance R 7 and triode Q3 to rear end switching on/electric capacity E2, the E3 charging, the voltage drop that current flowing resistance R7 produces is so that triode Q2 conducting, and triode Q2 conducting has limited again the conducting of triode Q3, thereby the electric current of limiting resistance R7 forms a crossing current circuit simultaneously.
8. intelligent electric meter, it comprises processor (10) and display circuit (20), it is characterized in that: further comprise power supply VCC, and relay switching on/control circuit as claimed in claim 1 (30), wherein capacitance-resistance voltage reduction circuit (1) connects power supply VCC and passes through its diode D3, and D4 is 24V with the magnitude of voltage clamper of power supply VCC; Described power supply VCC further is connected to display circuit (20), processor (10) and equalizer circuit (4) and operating voltage is provided for it; Described processor (10) is connected to equalizer circuit (4) by the ADC sample port and judges its switching on/electric capacity E2, and whether E3 charges complete to carry out the switching on/operation.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220557811 CN202917957U (en) | 2012-10-26 | 2012-10-26 | Relay switching-off and switching-on control circuit for ammeter and intelligent ammeter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201220557811 CN202917957U (en) | 2012-10-26 | 2012-10-26 | Relay switching-off and switching-on control circuit for ammeter and intelligent ammeter |
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| Publication Number | Publication Date |
|---|---|
| CN202917957U true CN202917957U (en) | 2013-05-01 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 201220557811 Expired - Fee Related CN202917957U (en) | 2012-10-26 | 2012-10-26 | Relay switching-off and switching-on control circuit for ammeter and intelligent ammeter |
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| CN (1) | CN202917957U (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102946088A (en) * | 2012-10-26 | 2013-02-27 | 华立仪表集团股份有限公司 | Switch-on/off control circuit for electric meter relay and intelligent electric meter |
| CN103513075A (en) * | 2013-10-10 | 2014-01-15 | 华立仪表集团股份有限公司 | Near-infrared reading device and electricity meter |
| CN105846671A (en) * | 2016-03-28 | 2016-08-10 | 柳州龙辉科技有限公司 | Power supply device for precise instrument |
-
2012
- 2012-10-26 CN CN 201220557811 patent/CN202917957U/en not_active Expired - Fee Related
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102946088A (en) * | 2012-10-26 | 2013-02-27 | 华立仪表集团股份有限公司 | Switch-on/off control circuit for electric meter relay and intelligent electric meter |
| CN102946088B (en) * | 2012-10-26 | 2015-04-01 | 华立仪表集团股份有限公司 | Switch-on/off control circuit for electric meter relay and intelligent electric meter |
| CN103513075A (en) * | 2013-10-10 | 2014-01-15 | 华立仪表集团股份有限公司 | Near-infrared reading device and electricity meter |
| CN103513075B (en) * | 2013-10-10 | 2016-04-27 | 华立科技股份有限公司 | near infrared reading device and ammeter |
| CN105846671A (en) * | 2016-03-28 | 2016-08-10 | 柳州龙辉科技有限公司 | Power supply device for precise instrument |
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| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20130501 Termination date: 20131026 |